The present invention relates to data networks and, more particularly, data networks including systems and methods for streaming multimedia applications, still more particularly, the present invention relates to networks including systems and methods for providing multicast transmissions, and for reception at a potentially large number of receiver locations.
Today, live and on-demand streaming multimedia objects are generally delivered over the Internet and other data networks via unicast connections. This architecture has many shortcomings, both from the content provider""s point of view and the user or recipient""s point of view. Thus, the content provider suffers a server load that increases linearly with the number of receivers. Users typically endure high start-up latency and unpredictable playback quality due to network congestion. In addition from an Internet service Provider""s (IsP""s) point of view, streaming multimedia under such a unicast architecture poses serious network congestion problems.
One way to partially address concerns of content providers and IsPs is to make use of IP multicast. By batching multiple requests into one multicast session, both server load and network load can be significantly reduced. Unfortunately, this solution does not address the receiver""s concerns. This is a direct consequence of a fundamental problem with multicast: In multicast, receivers are assumed to be homogeneous and synchronous. In reality, however, receivers are generally heterogeneous and asynchronous.
The limitations of the prior art are overcome and a technical advance is achieved in accordance with the present invention as disclosed in illustrative embodiments herein.
Illustrative embodiments of the present invention present a new architecture and operational techniques for supporting high quality live and on-demand streaming multimedia on a data network. By using Helper machines inside the network as data forwarding, caching, and buffering agents, and by dynamically formiing meshes among Helper machines, advantages of homogeneous, synchronous multicast transmission and of heterogeneous, asynchronous reception are achieved. In many applications, the architecture provides essentially transparent support to receivers for near-zero start-up latency, improved playback quality, improved VCR-like operations. These are achieved while reducing network and server load compared to today""s multimedia networking techniques. In addition, improved quality of service (QoS) is provided in respect of reduced jitter and packet loss. In many applications of the present inventive embodiments, modifications to the client software are not necessary.